package org.dant.ant.extension.net.soap;

import java.beans.*;
import java.io.*;
import java.util.*;
import java.lang.reflect.*;
import org.w3c.dom.*;
import org.apache.soap.util.*;
import org.apache.soap.util.xml.*;
import org.apache.soap.*;
import org.apache.soap.rpc.*;
import org.apache.soap.encoding.soapenc.*;

public class GenericBeanSerializer implements Serializer, Deserializer {
  
  public void marshall(String inScopeEncStyle, Class javaType, Object src,
                       Object context, Writer sink, NSStack nsStack,
                       XMLJavaMappingRegistry xjmr, SOAPContext ctx)
    throws IllegalArgumentException, IOException {
    nsStack.pushScope();
    SoapEncUtils.generateStructureHeader(inScopeEncStyle,
                                         javaType,
                                         context,
                                         sink,
                                         nsStack,
                                         xjmr);

    sink.write(StringUtils.lineSeparator);

    PropertyDescriptor[] properties = getPropertyDescriptors(javaType);
        
    for (int i = 0; i < properties.length; i++) {
      String propName = properties[i].getName();
      Class propType = properties[i].getPropertyType();
      
      // Serialize every property except the "class" property.
      if (!propType.equals(Class.class)) {
        Method propReadMethod = properties[i].getReadMethod();
        
        // Only serialize readable properties.
        if (propReadMethod != null) {
          Object propValue = null;
          
          // Get the property's value.
          try {
            if (src != null) {
              propValue = propReadMethod.invoke(src, new Object[]{});
            }
          } catch (Exception e) {
            throw new IllegalArgumentException("Unable to retrieve '" +
                                               propName + "' property " +
                                               "value: " + e.getMessage() +
                                               '.');
          }

          // Serialize the property.
          Parameter param = new Parameter(propName, propType, propValue, null);

          xjmr.marshall(Constants.NS_URI_SOAP_ENC, Parameter.class, param,
                        null, sink, nsStack, ctx);

          sink.write(StringUtils.lineSeparator);
        }
      }
    }

    sink.write("</" + context + '>');

    nsStack.popScope();
  }

  public Bean unmarshall(String inScopeEncStyle, QName elementType, Node src,
                         XMLJavaMappingRegistry xjmr, SOAPContext ctx)
    throws IllegalArgumentException {
    Element root = (Element)src;
    Element tempEl = DOMUtils.getFirstChildElement(root);
    Class javaType = xjmr.queryJavaType(elementType, inScopeEncStyle);
    Object bean = instantiateBean(javaType);
    PropertyDescriptor[] properties = getPropertyDescriptors(javaType);

    while (tempEl != null) {
      Bean paramBean = xjmr.unmarshall(inScopeEncStyle,
                                       RPCConstants.Q_ELEM_PARAMETER,
                                       tempEl, ctx);
      Parameter param = (Parameter)paramBean.value;
      Method propWriteMethod = getWriteMethod(param.getName(),
                                              properties,
                                              javaType);

      if (propWriteMethod != null) {
        // Set the property's value.
        try {
          propWriteMethod.invoke(bean, new Object[]{param.getValue()});
        } catch (Exception e) {
          throw new IllegalArgumentException("Unable to set '" +
                                             param.getName() +
                                             "' property: " +
                                             e.getMessage() + '.');
        }
      }

      tempEl = DOMUtils.getNextSiblingElement(tempEl);
    }

    return new Bean(javaType, bean);
  }


  private PropertyDescriptor[] getPropertyDescriptors(Class javaType)
    throws IllegalArgumentException {
    BeanInfo beanInfo = null;

    try {
      beanInfo = Introspector.getBeanInfo(javaType);
    } catch (IntrospectionException e) {
    }

    if (beanInfo != null) {
      PropertyDescriptor[] properties = beanInfo.getPropertyDescriptors();

      if (properties != null) {
        return properties;
      } else {
        throw new IllegalArgumentException("Unable to retrieve property " +
                                           "descriptors for '" +
                                           StringUtils.getClassName(javaType) +
                                           "'.");
      }
    } else {
      throw new IllegalArgumentException("Unable to retrieve BeanInfo " +
                                         "for '" + StringUtils.getClassName(
                                         javaType) + "'.");
    }
  }

  protected Method getWriteMethod(String propertyName,
                                       PropertyDescriptor[] pds,
                                       Class javaType) {
    for (int i = 0; i < pds.length; i++) {
      if (propertyName.equals(pds[i].getName())) {
        return pds[i].getWriteMethod();
      }
    }

    throw new IllegalArgumentException("Unable to retrieve " +
                                       "PropertyDescriptor for property '" +
                                       propertyName + "' of class '" +
                                       javaType + "'.");
  }

  private Object instantiateBean(Class javaType)
    throws IllegalArgumentException {
    try {
      return javaType.newInstance();
    } catch (Throwable t) {
      throw new IllegalArgumentException("***** Unable to instantiate '" +
                                         StringUtils.getClassName(javaType) +
                                         "': " + t.getMessage());
    }
  }
}

